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1.
Int J Syst Evol Microbiol ; 70(3): 2155-2157, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31922468

RESUMO

Under Rule 23a (Note 4) of the Bacteriological Code we ask the Judicial Commission to issue an opinion that will correct two errors that were made on the original 1980 Approved Lists of Bacterial Names. We request that the type strain designations for Aeromonas punctata and Aeromonas punctata subsp. punctata be corrected from ATCC 15468T to NCMB 74T. We also ask that the opinion state the 'correct' or best way to write the author citations for several other Aeromonas names in order to avoid future instability in nomenclature when the citations are given.


Assuntos
Aeromonas/classificação , Filogenia
2.
Int J Syst Evol Microbiol ; 70(3): 2158-2162, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31935185

RESUMO

In a companion paper, we requested the Judicial Commission to correct the type strain of Aeromonas punctata from ATCC 15468T to NCMB 74T (=ATCC 23309T). Correction of this error on the 1980 Approved Lists by an Opinion of the Judicial Commission will remove the status of the name Aeromonas caviae as a junior objective synonym of A. punctata. This is important because the scientific community continues to use the name A. caviae almost exclusively instead of A. punctata. However, the corrective action of this Opinion will cause a new problem. A. punctata and A. eucrenophila will then become objective synonyms because both species will have the same type strain NCMB 74T, and A. punctata would have priority because it was published first (1890 vs. 1987). Thus, A. punctata rather than A. eucrenophila would become the correct name for DNA hybridization group 6. A. punctata has had a very confusing history since it was first described as Bacillus punctatus by Zimmermann in 1890. It was without a type strain for over 50 years, and unfortunately, has had an incorrect type strain for some 40 years. The name A. punctata as a bacterial species has been used incorrectly in the literature very frequently, either based on the wrong type strain or with the wrong definition or circumscription. The name A. punctata is not accepted or used by most specialists who study and publish scientific papers and reviews on Aeromonas. Under the heading 'Rejection of Names' Rule 56a of the Bacterial Code states reasons why the Judicial Commission can reject a name, the first is: '(1) An ambiguous name (nomen ambiguum), i.e., a name which has been used with different meanings and thus has become a source of error'. Rule 56a gives the Judicial Commission authority to place names on the list of rejected names. Our analysis of its history leads us to state unequivocally that A. punctata currently is, and has been throughout the vast majority of its history, an ambiguous name. After considering all the possible alternatives and their consequences we request the Judicial Commission to go against the rules of priority; to invoke case (1) of Rule 56a, and issue an Opinion conserving A. eucrenophila over A. punctata; and to place the name A. punctata on the list of rejected names. We argue that these actions will give instant stability to a complex and confusing situation by making A. eucrenophila rather than A. punctata the correct name for 'Aeromonas DNA hybridization group 6', an association that is almost universally accepted by the scientific community as reflected in the literature.


Assuntos
Aeromonas/classificação , Filogenia , DNA Bacteriano/genética , Hibridização de Ácido Nucleico
3.
Ecotoxicol Environ Saf ; 191: 110182, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31958628

RESUMO

The gut of aquatic animals was a significant niche for dissemination of antibiotic resistance genes (ARGs) and direct response of living conditions. In this study, the gut microbiota of goldfish Carassius auratus Linnaeus was sampled at 7 days and 21 days after treatment with tetracycline at 0.285 and 2.85 µg L-1 to investigate the influences on the microbial structure and antibiotic resistance. The proportion of tetracycline resistance bacteria was 1.02% in the control group, while increased to 23.00%, 38.43%, 62.05% in groups of high concentration for 7 days (H7), low concentration for 21 days (L21) and high concentration for 21 days (H21), respectively. Compared to the control group, the diversity of isolated Aeromonas spp. was decreased in the treatment groups and the minimal inhibitory concentration (MIC) of resistant isolates was enhanced from 32 to 256 µg mL-1 with the treatment of tetracycline in time- and dose-dependent manners. Furthermore, the abundance of most genes was increased in treatment groups and efflux genes mainly responded to the stress of tetracycline with an average level of 1.0 × 10-2. After treatment with tetracycline, the predominant species were changed both at phylum and genus levels. The present study explored the impact of tetracycline on gut microbiota of goldfish at environmentally realistic concentrations for the first time and our findings will provide a reference for characterizing the microbiome of fish in the natural environment.


Assuntos
Aeromonas/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Carpa Dourada/microbiologia , Resistência a Tetraciclina/genética , Tetraciclina/toxicidade , Aeromonas/classificação , Aeromonas/genética , Aeromonas/isolamento & purificação , Animais , Antibacterianos/toxicidade , Exposição Ambiental/efeitos adversos , Genes Bacterianos , Testes de Sensibilidade Microbiana , Resistência a Tetraciclina/efeitos dos fármacos
4.
BMC Infect Dis ; 20(1): 60, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31959118

RESUMO

BACKGROUND: Necrotizing fasciitis (NF) is a rare and life-threatening necrotizing skin and soft-tissue infection. Infectious pathogens of NF must be detected early and treated rapidly to prevent loss of limb or a fatal outcome. This study aimed to detect more reliable predictors between gram-negative and gram-positive monomicrobial NF of limbs. METHODS: A total of 100 patients with limb monomicrobial NF were diagnosed prospectively from April 2015 to July 2018. These monomicrobial NF pathogens can be divided into gram-negative and gram-positive groups according to the result of Gram staining and final bacterial reports. Data such as demographics, seawater or seafood contact history, infectious location, comorbidities, presenting signs and symptoms, and laboratory findings were recorded and compared. RESULTS: A total of 55 patients were infected with gram-negative organisms and 45 patients with gram-positive organisms. Among the 55 cases of monomicrobial gram-negative NF, 48 (87.3%) were caused mainly by Vibrio spp. (38, 69.1%) and Aeromonas spp. (10, 18.2%). A higher incidence of chronic kidney disease, cerebrovascular accident, tachypnea, and septic shock; a higher rate of band forms of leukocytes of more than 3%, serum lactate of more than 20 mg/dL, and C-reactive protein level of less than 150 mg/dL; prolonged prothrombin time; and a lower fibrinogen level were observed in patients with gram-negative infection. In a multivariate analysis, a higher incidence of seawater or seafood contact history (odds ratio [OR]: 66.301; 95% confidence interval [CI]: 7.467-588.702), a higher rate of hyperlactatemia (OR: 7.904; 95% CI: 1.231-50.744), and a low fibrinogen level (OR: 1.013; 95% CI: 1.004-1.023) indicated gram-negative infection. CONCLUSIONS: In southern Taiwan, NF of limbs mainly affected the lower limbs, exhibited monomicrobial infection, and was predominated by gram-negative bacteria. Gram-negative monomicrobial NF of limbs often occurred in individuals with the more seawater or seafood contact history, hyperlactatemia, and low fibrinogen levels.


Assuntos
Aeromonas/isolamento & purificação , Fasciite Necrosante/epidemiologia , Fasciite Necrosante/microbiologia , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções dos Tecidos Moles/epidemiologia , Infecções dos Tecidos Moles/microbiologia , Vibrio/isolamento & purificação , Idoso , Idoso de 80 Anos ou mais , Fasciite Necrosante/diagnóstico , Feminino , Infecções por Bactérias Gram-Negativas/diagnóstico , Humanos , Incidência , Extremidade Inferior/microbiologia , Extremidade Inferior/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Infecções dos Tecidos Moles/diagnóstico , Taiwan/epidemiologia
5.
Ecotoxicol Environ Saf ; 191: 110155, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31972452

RESUMO

Soils in the water-level-fluctuating zone (WLFZ) of Three Gorges Reservoir (TGR) inundated by water for different periods of time are confirmed to have disparate characteristics to mercury (Hg), and thus it is of great significance to further investigate microbial compositions and influencing factors. The objective of this study was to compare bacterial and archaeal richness, α-diversities and compositions, as well as affecting variables, especially Hg concentrations, among soils under different submergence time-SI (inundated soil), SS (semi-inundated soil), SN(non-inundated soil) and SSe (sediment)-based on high throughput sequencing. Results showed that sediment had significantly higher bacterial and archaeal richness and α-diversities than the other soil types. Anaerolinea and Aeromonas, as well as Altiarchaeales, Nitrosoarchaeum, and Methanosarta were dominant in SSe, while sharply decreasing in the other soil types, with significant difference among groups. An unclassified genus in SCG critically predominating in SI, SS and SN, drastically reduced in SSe, with extremely significant difference among groups. Bathyarchaeota and Nitrososphaera, both dominating in SSe, decreased dramatically and almost vanished in SI and SN. All the variables except pH posed a significant positive effect on bacterial and archaeal compositions in SSe, while opposite effect in the other three soil types. MeHg and THg concentrations had relatively weaker effects on microbial compositions comparing to variables like NH4+, CEC, OM and SO42+.


Assuntos
Aeromonas/crescimento & desenvolvimento , Archaea/crescimento & desenvolvimento , Monitoramento Ambiental/métodos , Mercúrio/análise , Poluentes do Solo/análise , Poluentes Químicos da Água/análise , China , Água Doce/química , Solo/química
6.
J Appl Microbiol ; 128(2): 606-617, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31606917

RESUMO

AIMS: The object of this study was to identify potential health concerns of the Aeromons spp. isolated from marketed Pacific abalone (Haliotis discus hannai) with respect to their virulence and antimicrobial resistance patterns. METHODS AND RESULTS: We identified 29 strains of aeromonads consisting of five species; Aeromonas hydrophila (n = 9), Aeromonas enteropelogenes (n = 14), Aeromonas veronii (n = 3), Aeromonas salmonicida (n = 2) and Aeromonas sobria (n = 1), by employing series of biochemical tests and gene sequencing. In the phenotypic virulence assays, all isolates showed gelatinase and caseinase activities, while lipase formation (69%), phospholipase production (90%), DNase formation (82%), slime production (49%) and haemolysis activity (α = 18% and ß = 82%) were also detected among isolates. Prevalence of virulence genes; aerA (100%), fla (66%), ahyB (73%), act (52%), alt (42%), ast (35%), ser (52%), gcat (69%), ascV (43%), hlyA (83%), lip (52%) and exu (59%) were detected by PCR assays. In disc diffusion test, 100% resistance was detected against ampicillin while cephalothin, rifampicin, oxytetracycline, colistine sulphate, nalidixic acid and piperaciliin were resisted by 86, 73, 42, 35, 28, 20 and 20% of the isolates respectively. Thirteen (45%) of the isolates showed multiple antimicrobial resistance (MAR) indices ≥ 0·2. CONCLUSIONS: Our findings suggest that the potential health risk posed by the abalone-borne Aeromonas spp. should not be underestimated. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first time to evaluate possible public health risks upon consumption of abalone harbored Aeromonas spp. and also to isolate potential pathogenic and multidrug-resistant Aeromonas spp. from Pacific abalone in Korea.


Assuntos
Aeromonas/efeitos dos fármacos , Aeromonas/isolamento & purificação , Farmacorresistência Bacteriana , Gastrópodes/microbiologia , Alimentos Marinhos/microbiologia , Aeromonas/classificação , Aeromonas/genética , Animais , Antibacterianos/farmacologia , Contaminação de Alimentos/análise , Ácido Nalidíxico/farmacologia , Fosfoproteínas Fosfatases/genética , Fosfoproteínas Fosfatases/metabolismo , Reação em Cadeia da Polimerase , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , República da Coreia
7.
Food Chem ; 305: 125454, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31505413

RESUMO

The effects of the (-)-Epigallocatechin gallate (EGCG)-gelatin biofilm treatment (EGT) on microbial composition and quality of tilapia fillets stored at low temperatures were evaluated. The changes in mechanical properties, microbial reproduction, as well as lipid and protein oxidation during fillets storage were determined. The results showed that EGT reduced the microbial count and the relative abundance of the fillets. And EGT delayed the rate of lipid oxidation and protein denaturation in fillets. Compared with the control group, EGT samples had lower K values (74% on 18 d) and biogenic amines (39 mg/kg for putrescine and 50 mg/kg for cadaverine on 21 d). According to sensory evaluation, the shelf life of tilapia fillets was extended by 6 d in the EGT group. Therefore, EGT improved the quality of cryopreserved tilapia fillets and could be considered as a potential method for fish fillet preservation.


Assuntos
Materiais Biomiméticos/química , Catequina/análogos & derivados , Armazenamento de Alimentos/métodos , Gelatina/química , Alimentos Marinhos/análise , Aeromonas/efeitos dos fármacos , Animais , Aminas Biogênicas/análise , Materiais Biomiméticos/farmacologia , Catequina/química , Peroxidação de Lipídeos/efeitos dos fármacos , Desnaturação Proteica/efeitos dos fármacos , Proteínas/química , Pseudomonas/efeitos dos fármacos , Alimentos Marinhos/microbiologia , Paladar/efeitos dos fármacos , Temperatura
8.
Lett Appl Microbiol ; 70(3): 221-229, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31854000

RESUMO

Hard-shelled mussel (Mytilus coruscus) is a popular seafood in Korea. This study aimed to determine the virulence markers and antimicrobial resistance patterns of 33 Aeromonas strains isolated from mussels. The isolates were identified as A. salmonicida (n = 14), A. veronii (n = 9), A. enteropelogenes (n = 4), A. caviae (n = 3), A. allosaccharophila (n = 2) and A. bivalvium (n = 1) by gyrB gene sequencing. The sequence divergence between and within the species ranged from 3·70 to 10·40% and 0-1·50% respectively. Every species formed a distinct group in a neighbour-joining phylogenetic tree. The DNase, gelatinase, caseinase, ß-haemolysis, biofilm and lipase activities were observed in 33 (100·00%), 31 (93·93%), 30 (90·90%), 27 (81·81%), 21 (63·63%) and 17 (51·51%) isolates respectively. The virulence genes were detected by PCR in the following frequencies: fla (90·09%), aer (87·88%), hlyA (87·88%), ahyB (81·19%), gcaT (75·76%), ser (69·70%), lip (66·67%), alt (57·58%), ast (51·51%) and act (21·21%). Every isolate was resistant to at least three of 18 antimicrobials in the disk diffusion test. The multiple antimicrobial resistance index values ranged from 0·11 to 0·44 among the isolates. Our study suggests that mussels can be a potential reservoir of virulent and multidrug-resistant Aeromonas sp. SIGNIFICANCE AND IMPACT OF THE STUDY: Aeromonas sp. are known as common pathogenic bacteria isolated from seafood. The virulence factors and antimicrobial resistance profiles of mussel-borne Aeromonas sp. are poorly understood. This study demonstrated for the first time the existence of virulence markers and antimicrobial resistance of Aeromonas sp. from mussels in Korea. Majority of the isolates were positive for phenotypic virulence characteristics and harboured several virulence genes which reveal the potential virulence of mussel-borne Aeromonas sp. Multiple antimicrobial resistance was also observed among the isolates. Our study highlights the importance of food safety standards in mussel consumption.


Assuntos
Aeromonas/classificação , Aeromonas/isolamento & purificação , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Mytilus/microbiologia , Aciltransferases/genética , Aeromonas/genética , Aeromonas/patogenicidade , Animais , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Infecções por Bactérias Gram-Negativas/microbiologia , Lipase/genética , Filogenia , Reação em Cadeia da Polimerase , República da Coreia , Alimentos Marinhos/microbiologia , Virulência/genética , Fatores de Virulência/genética
9.
Food Microbiol ; 86: 103356, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31703863

RESUMO

Quorum sensing (QS), bacterial cell-to-cell communication, is a gene regulatory mechanism that regulates virulence potential and biofilm formation in many pathogens. Aeromonas sobria, a common aquaculture pathogen, was isolated and identified by our laboratory from the deteriorated turbot, and its potential for virulence factors and biofilm production was regulated by QS system. In view of the interference with QS system, this study was aimed to investigate the effect of methyl anthranilate at sub-Minimum Inhibitory Concentrations (sub-MICs) on QS-regulated phenotypes in A. sobria. The results suggested that 0.5 µL/mL of methyl anthranilate evidently reduced biofilm formation (51.44%), swinging motility (74.86%), swarming motility (71.63%), protease activity (43.08%), and acyl-homoserine lactone (AHL) production. Furthermore, the real-time quantitative PCR (RT-qPCR) and in silico analysis showed that methyl anthranilate might inhibit QS system in A. sobria by interfering with the biosynthesis of AHL, as well as competitively binding with receptor protein. Therefore, our data indicated the feasibility of methyl anthranilate as a promising QS inhibitor and anti-biofilm agent for improving food safety.


Assuntos
Aeromonas/efeitos dos fármacos , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Percepção de Quorum/efeitos dos fármacos , ortoaminobenzoatos/farmacologia , 4-Butirolactona/análogos & derivados , 4-Butirolactona/metabolismo , Aeromonas/genética , Aeromonas/fisiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
10.
Food Microbiol ; 86: 103313, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31703873

RESUMO

This study investigated the effect of phytic acid and lysozyme on the microbial composition and quality of grass carp (Ctenopharyngodon idellus) fillets stored at 4 °C. The control, 0.5 mg/mL lysozyme-treated fillets (T1), 0.5 mg/mL phytic acid-treated fillets (T2) and 0.25 mg/mL lysozyme + 0.25 mg/mL phytic acid-treated fillets (T3) were evaluated based on sensory assessment, biogenic amines, ATP-related compounds, total volatile basic nitrogen (TVB-N), and total viable counts (TVC). Changes in microbial composition were analyzed using high-throughput sequencing. Results showed that phytic acid and lysozyme treatment delayed the decrease in sensory scores, reduced the rate of degradation of IMP to Hx, inhibited the growth of microorganisms, and attenuated the increase in TVB-N and putrescine. Phytic acid exhibited better preservation effects than lysozyme and their combination was more effective than using either alone. High-throughput sequencing showed that Acinetobacter and Kocuria were the predominant bacteria in fresh grass carp, but Pseudomonas rose rapidly with storage time; Pseudomonas, Shewanella, and Aeromonas constituted the main spoilage bacteria of grass carp fillets. Lysozyme treatment significantly reduced the proportion of Shewanella and Acinetobacter, and phytic acid and the combination of phytic acid and lysozyme significantly reduced the proportion of Pseudomonas in spoiled grass carp fillets.


Assuntos
Carpas/microbiologia , Produtos Pesqueiros/microbiologia , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Microbiota/efeitos dos fármacos , Muramidase/farmacologia , Ácido Fítico/farmacologia , Acinetobacter/efeitos dos fármacos , Acinetobacter/crescimento & desenvolvimento , Aeromonas/efeitos dos fármacos , Aeromonas/crescimento & desenvolvimento , Animais , Aminas Biogênicas/análise , Conservação de Alimentos/instrumentação , Armazenamento de Alimentos , Humanos , Pseudomonas/efeitos dos fármacos , Pseudomonas/crescimento & desenvolvimento , Shewanella/efeitos dos fármacos , Shewanella/crescimento & desenvolvimento , Paladar
11.
Afr Health Sci ; 19(2): 2036-2042, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31656487

RESUMO

Background: Aeromonas are ubiquitous bacteria causing many clinical conditions including acute diarrhea. Diarrheagenic Aeromonas harbors aerolysin gene secreting virulent enterotoxin, aerolysin. Objectives: To develop a molecular and immunological based method for detection of Aeromonas. Methods: Diarrheal Aeromonas strains were identified from stool samples using culture, enterotoxicity testing using mice model. During immune magnetic polymerase chain reaction IM-PCR protocol, aerolysin specific antibodies were bound with immuno magnetic binding. Sensitivity and specificity tests for IM-PCR were conducted. Results: There was high detection of Aeromonas using IM-PCR (12.4 %) technique when compared to low isolation with culture (5.1%). Our study confirmed that some strains of enterotoxic Aeromonas strains were uncultivable. Enterotoxicity tests on culture isolates revealed many strains were negative. IM-PCR detected high, (62/500) rate of identification of Aeromonas with aerolysin toxin gene. Aeromonas species identified after IM-PCR were A. hydrophila (40.3% ), A. veronii (17.7 %), A. caviae (14.5 %), A. trota (11.2 %), A. jandei (9.6 %) and A. schuberti (6.4%). All A. trota strains were undetected by cultivation. Conclusion: High sensitivity and specificity of IM-PCR are due to preparation of aerolysin antibodies and immuno magnetic binding, prior to PCR. Since diseases due to Aeromonas are increasingly reported, IM-PCR is recommended for detection from clinical specimens.


Assuntos
Aeromonas/genética , Toxinas Bacterianas/genética , Diarreia/microbiologia , Reação em Cadeia da Polimerase/métodos , Proteínas Citotóxicas Formadoras de Poros/genética , Aeromonas/isolamento & purificação , Animais , Etiópia , Genes Bacterianos , Humanos , Fenômenos Magnéticos , Camundongos , Coelhos , Sensibilidade e Especificidade
12.
Int J Antimicrob Agents ; 54(6): 798-802, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31600552

RESUMO

OBJECTIVE: It is important to understand the origins of antibiotic resistance genes so that risks associated with the emergence of novel resistance genes can be assessed and managed. The chromosomal ampC gene (CAV-1) of Aeromonas caviae (A. caviae) has been reported as the origin of mobile FOX cephalosporinases. The recent identification of A. caviae as the origin of MOX-2 cephalosporinases and the comparably great sequence divergence between FOX and MOX genes makes it unlikely that both genes arose from the same species. Therefore, this study investigated the origin of FOX cephalosporinases using large-scale genomics. METHODS: Publicly available genomes and plasmids were searched for FOX-like genes. Synteny and nucleotide identities of the identified FOX-like genes and their genetic environments were compared and a phylogenetic tree was generated. RESULTS: FOX-like genes were identified in > 230 Aeromonas genomes and in 46 Enterobacteriaceae isolates. Analysis of the genomic context of CAV-1 revealed a truncated insertion sequence directly upstream of the ampC gene. The chromosomal ampCs of A. caviae (n = 31) were 75-78% identical to CAV-1. In contrast, CAV-1, mobile FOX genes and their context were 95-98% similar to the chromosomal ampC-locus of Aeromonas allosaccharophila (A. allosaccharophila) (n = 6). The A. allosaccharophila ampCs formed a monophyletic branch with mobile FOX genes, whereas the A. caviae ampCs clustered with mobile MOX genes. CONCLUSIONS: These findings show that FOX cephalosporinases originate not in A. caviae, as previously reported, but in A. allosaccharophila, which is a fish pathogen. This finding agrees with the hypothesis that antibiotic use in aquaculture could have contributed to the emergence of FOX genes in human pathogens.


Assuntos
Aeromonas/enzimologia , Aeromonas/genética , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana/genética , beta-Lactamases/genética , Proteínas de Bactérias/classificação , Elementos de DNA Transponíveis , Enterobacteriaceae/genética , Regulação Bacteriana da Expressão Gênica , Genoma Bacteriano , Filogenia , beta-Lactamases/classificação
13.
J Fish Dis ; 42(12): 1637-1644, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31578759

RESUMO

Doctor fish (Garra rufa, Heckel, 1843) are increasingly used for cosmetic treatment raising particular concerns regarding the potential transmission of infections to clients. Investigations of microbial causes undertaken in two outbreaks of mortality among G. rufa used for cosmetic treatment revealed the presence of multiple bacteria, including both fish and human pathogens such as Aeromonas veronii, A. hydrophila, Vibrio cholerae, Shewanella putrefaciens, Mycobacterium marinum and M. goodii. This range of bacteria indicates an intense microbial proliferation involving multiple pathogens, most likely induced by the poor health condition of the fish. Most of the detected pathogens are well-known agents of zoonosis. Indeed, M. goodii is an emerging nosocomial human pathogen that has never been detected in fish to date, nor in other animals. This first detection of M. goodii associated with fish infection points out a new zoonotic potential for this pathogen. These findings point out that handling, poor environmental conditions and the presence of fish pathogens, that can compromise the immune system of fish, can result in a mixed microbial proliferation and increase the spread of waterborne bacteria, including zoonosis agents. Accordingly, the microbiological surveillance of fish used for cosmetic treatment is extremely important, particularly in association with mortality outbreaks.


Assuntos
Cyprinidae/microbiologia , Doenças dos Peixes/microbiologia , Aeromonas/isolamento & purificação , Animais , Técnicas Cosméticas , Surtos de Doenças/veterinária , Doenças dos Peixes/mortalidade , Humanos , Mycobacteriaceae/isolamento & purificação , Shewanella putrefaciens/isolamento & purificação , Vibrio cholerae/isolamento & purificação , Zoonoses/microbiologia
14.
Arq. bras. med. vet. zootec. (Online) ; 71(5): 1609-1615, set.-out. 2019. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1038678

RESUMO

Objetivou-se avaliar a ocorrência de Aeromonas spp. em peixes e amostras de água na região semiárida de Pernambuco e avaliar a frequência de aerolissina (aerA), enterotoxina citotóxica (act), enterotoxina citotônica (alt) e serina protease (ahp) nesses isolados. Foram analisados 70 peixes vivos e oito mortos com sinais clínicos de aeromoniose e 16 amostras de água. Aeromonas spp. foram identificadas por análises microbiológicas (provas bioquímicas) e molecular, usando-se primers específicos para a região 16S rRNA, e a distribuição dos quatro fatores de virulência (aerA, alt, act e ahp) foi investigada por ensaio de PCR. Cento e cinquenta e cinco (84,7%) isolados foram confirmados como Aeromonas spp. na análise molecular. Os genes de virulência mais frequentes foram act (53,55%) e aerA (51,61%). De acordo com o tipo de amostra, observou-se maior frequência do gene aerA (87,5% P=0,0474) em isolados de peixes mortos e a menor frequência do gene act (47,73% P=0,0002) em peixes vivos. Este estudo demonstrou a presença de aeromoniose no cultivo de tilápias em tanques-rede, nos municípios de Jatobá e Petrolândia, na região semiárida de Pernambuco. A detecção de aerA, act e alt pode ser utilizada na tipagem de virulência de Aeromonas spp.(AU)


The purpose of this study was to evaluate the occurrence of Aeromonas spp. from fishes and tilapia net-cage farm water in semi-arid regions of Pernambuco and to evaluate the frequency of the aerolysin (aerA), cytotoxic enterotoxin (act), cytotonic enterotoxin (alt) and serine protease (ahp) genes in Aeromonas isolates. 70 live and eight dead fish with aeromoniosis clinical signs and 16 water samples were analyzed. Aeromonas spp. isolated were identified by microbiological (biochemical evidence) and molecular analysis using specific primers for 16SrRNA region, while the distribution of four virulence factors, including aerA, alt, act and ahp, was investigated by PCR assay. One hundred fifty-five (84.7%) isolates were confirmed as Aeromonas spp. by molecular analysis. The most frequent virulence genes in isolates were act (53.55%) and aerA (51,61%). According to the kind of sample, the higher frequency of aerA gene (87.5% P= 0.0474) was observed in isolates from dead fish and the lowest frequency of act gene (47.73% P= 0.0002) from live fish. This study found the presence of aeromoniosis on tilapia farming in net-cages on Jatobá and Petrolândia counties in the semiarid Pernambuco region. The detection of aerA, act and alt can be used for virulence typing of Aeromonas spp. isolates.(AU)


Assuntos
Animais , Tilápia/microbiologia , Aeromonas/patogenicidade , Ciclídeos/microbiologia , Pesqueiros , Virulência
15.
Braz J Infect Dis ; 23(5): 336-342, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31541615

RESUMO

INTRODUCTION: Aeromonas species are renowned enteric pathogens with virulence determinants linked to human diseases, such as gastroenteritis, skin, soft-tissue and muscle infections, and septicemia. A recent concern of resistance in this organism has emerged, especially the presence carbapenemases. Herein we describe a case series of emerging carbapenem-resistant Aeromonas species infection in our hospital in Cali, Colombia. MATERIALS AND METHODS: Cases from 2012 to 2018 are reported. Clinical data was abstracted from the clinical charts and laboratory information. Phenotypic detection of resistance was identified using the VITEK®2 system (BioMérieux) and broth microdilution MicroScan WalkAway plus System (Beckman Coulter). CARBA NP-test and multiplex qPCR assay was performed in 11 isolates to identify genes encoding carbapenemases (blaKPC, blaVIM, blaIMP and blaNDM). RESULTS: 21 cases of Aeromonas infection in hospitalized patients with phenotypic resistance to carbapenems were studied. The median age was 50 years, 55% (12/21) were male, and 67% (14/21) were healthcare-associated infections (HAI). Aeromonas hydrophila was the most common species (19/21). Forty-three percent (9/21) of the patients were immunocompromised. The mortality was 33% (7/21), and in patients with bacteremia was 100%. Most patients received empirical treatment with meropenem and failed to this treatment. PCR amplification tests showed negative results for the carbapenemases analyzed. CONCLUSION: Emerging phenotypic carbapenem-resistant infection has been seen in our hospital, most as HAI. High mortality was found, especially in immunocompromised patients and in those who failled empirical treatment with carbapenems. As the main carbapenemases tested were negative, carbapenem-resistant could be attributed to an intrinsic metallo-ß-lactamase, CphA encoded by the cphA gene, possible hyperproduction of ampC ß-lactamase and/or porins expression.


Assuntos
Aeromonas/genética , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Infecções por Bactérias Gram-Negativas/microbiologia , Resistência beta-Lactâmica/genética , beta-Lactamases/genética , Adulto , Aeromonas/efeitos dos fármacos , Aeromonas/enzimologia , Idoso , Colômbia , Estudos Transversais , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Fenótipo
16.
PLoS One ; 14(8): e0221344, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31419250

RESUMO

Aeromonas sobria is a pathogen causing food-borne illness. In immunocompromised patients and the elderly, A. sobria can leave the intestinal tract, and this opportunistically leads to severe extraintestinal diseases including sepsis, peritonitis, and meningitis. To cause such extraintestinal diseases, A. sobria must pass through the intestinal epithelial barrier. The mechanism of such bacterial translocation has not been established. Herein we used intestinal (T84) cultured cells to investigate the effect of A. sobria serine protease (ASP) on junctional complexes that maintain the intercellular adhesion of the intestinal epithelium. When several A. sobria strains were inoculated into T84 monolayer grown on Transwell inserts, the strain with higher ASP production largely decreased the value of transepithelial electrical resistance exhibited by the T84 monolayer and markedly caused bacterial translocation from the apical surface into the basolateral side of T84 monolayer. Further experiments revealed that ASP acts on adherens junctions (AJs) and causes the destruction of both nectin-2 and afadin, which are protein components constituting AJs. Other studies have not revealed the bacterial pathogenic factors that cause the destruction of both nectin-2 and afadin, and our present results thus provide the first report that the bacterial extracellular protease ASP affects these molecules. We speculate that the destruction of nectin-2 and afadin by the action of ASP increases the ability of A. sobria to pass through intestinal epithelial tissue and contributes to the severity of pathological conditions.


Assuntos
Aeromonas/patogenicidade , Proteínas de Bactérias/metabolismo , Doenças Transmitidas por Alimentos/patologia , Mucosa Intestinal/patologia , Serina Proteases/metabolismo , Aeromonas/metabolismo , Translocação Bacteriana , Técnicas de Cultura de Células , Linhagem Celular , Doenças Transmitidas por Alimentos/microbiologia , Humanos , Mucosa Intestinal/citologia , Cinesina/metabolismo , Miosinas/metabolismo , Nectinas/metabolismo
17.
Rev Fac Cien Med Univ Nac Cordoba ; 76(3): 154-158, 2019 08 29.
Artigo em Espanhol | MEDLINE | ID: mdl-31465182

RESUMO

Introduction: Aeromonas is a common cause of gastroenteritis but occasionally it can cause extraintestinal infections. The incidence of bacteremia by this genus is very low and in general the patients have associated base diseases. Materials and methods: Retrospective analysis of episodes of bacteremia by Aeromonas spp. during a period of eight years in the National Hospital of Clinics of the city of Córdoba, emphasizing age, sex, associated comorbidities, clinical presentation, focus, origin of the infection, clinical evolution, species prevalence and antimicrobial sensitivity of the same . Results: 10 episodes of bacteremia were recorded by Aeromonas spp. 60% corresponded to women and 40% to men. The average age was 65 years. In seven patients the origin of the infection was community and in three nosocomial. 70% of the patients presented predisposing base pathologies. The focus of bacteremia was abdominal in two cases. A. hydrophila complex was responsible for 50% of the cases. 80% of bacteremia were monomicrobial. The isolates generally showed high percentages of sensitivity. Conclusion: Bacteremia occurred in elderly patients of both sexes, most of whom had associated comorbidities. The majority of the infections originated in the community. While bacteremia by Aeromonas spp. it is rare, the mortality found in our study was relatively high despite the high percentage of sensitivity to antimicrobials.


Assuntos
Aeromonas/isolamento & purificação , Bacteriemia/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/classificação , Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Bacteriemia/epidemiologia , Comorbidade , Resistência a Medicamentos , Feminino , Hospitais Universitários , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
19.
J Food Sci ; 84(8): 2250-2255, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31313323

RESUMO

The ability to produce various extracellular enzymes is considered as an important virulence feature in Aeromonas spp., in addition to producing specific virulence factors such as aerolysin and hemolysin. In this study, the effect of salinity and pH on the production of extracellular virulence factors by Aeromonas was investigated. Aeromonas was obtained from different food sources. A comparative study of the activities of extracellular enzymes secreted by these bacteria at different environmental conditions can widen our understanding on their pathogenicity. The activities of various extracellular enzymes such as amylase, gelatinase, and caseinase, which are implicated as virulence factors, were measured in vitro by calculating the enzymatic activity index (EAI) of each enzyme using standard laboratory protocols. For all enzymes, a significant change (P < 0.05) in the EAI was observed when the concentration of NaCl in the media increased from 0.5% to 3%. Among three enzymes tested, caseinase was found to be affected the most by salinity, with a significant difference in EAI when NaCl concentration in the media increased from 0.5% to 2%. Similarly, amylase was found to be affected the most by acidity. The pH values ranging from 6 to 9 did not exert any significant change in EAI of amylase; however, a pH value of 5 had a significant effect. Overall, compared to salinity, the change in pH was found to be less effective in controlling the extracellular virulence factor production in Aeromonas. PRACTICAL APPLICATIONS: The practical application is to minimize the extracellular virulence factor production by Aeromonas in food commodities by altering the salt content and pH. The results demonstrate that an increase in salinity and a decrease in pH can minimize the extracellular virulence factor production by Aeromonas spp.


Assuntos
Aeromonas/metabolismo , Proteínas de Bactérias/metabolismo , Cloreto de Sódio/metabolismo , Fatores de Virulência/metabolismo , Aeromonas/genética , Proteínas de Bactérias/genética , Toxinas Bacterianas/genética , Toxinas Bacterianas/metabolismo , Microbiologia de Alimentos , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Concentração de Íons de Hidrogênio , Proteínas Citotóxicas Formadoras de Poros/genética , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Salinidade , Cloreto de Sódio/análise , Fatores de Virulência/genética
20.
PLoS One ; 14(6): e0214035, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31163020

RESUMO

The genetic determinants of bacterial pathogenicity are highly variable between species and strains. However, a factor that is commonly associated with virulent Gram-negative bacteria, including many Aeromonas spp., is the type 3 secretion system (T3SS), which is used to inject effector proteins into target eukaryotic cells. In this study, we developed a bioinformatics pipeline to identify T3SS effector proteins, applied this approach to the genomes of 105 Aeromonas strains isolated from environmental, mutualistic, or pathogenic contexts and evaluated the cytotoxicity of the identified effectors through their heterologous expression in yeast. The developed pipeline uses a two-step approach, where candidate Aeromonas gene families are initially selected using Hidden Markov Model (HMM) profile searches against the Virulence Factors DataBase (VFDB), followed by strict comparisons against positive and negative control datasets, greatly reducing the number of false positives. This approach identified 21 Aeromonas T3SS likely effector families, of which 8 represent known or characterized effectors, while the remaining 13 have not previously been described in Aeromonas. We experimentally validated our in silico findings by assessing the cytotoxicity of representative effectors in Saccharomyces cerevisiae BY4741, with 15 out of 21 assayed proteins eliciting a cytotoxic effect in yeast. The results of this study demonstrate the utility of our approach, combining a novel in silico search method with in vivo experimental validation, and will be useful in future research aimed at identifying and authenticating bacterial effector proteins from other genera.


Assuntos
Aeromonas/patogenicidade , Sistemas de Secreção Tipo III/metabolismo , Fatores de Virulência/toxicidade , Aeromonas/genética , Aeromonas/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/toxicidade , Biologia Computacional/métodos , Simulação por Computador , Genoma Bacteriano , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/efeitos dos fármacos , Fatores de Virulência/genética
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